Arrow keys not working in tmux from PuTTY


I SSH into a Ubuntu computer from a Windows computer using PuTTY. I run tmux (actually byobu which runs tmux underneath) and at a shell inside tmux I find that the left and right arrow keys do not work. They are actually detected as shift+left and shift+right arrow keys inside tmux.


This problem has been discussed here. One of the suggested solutions was to add set enable-keypad on to ~/.inputrc. That did not seem to work for me.

However, the above bug report also mentioned that this was a bug in tmux and it was fixed in tmux 2.4. So, I used this tmux PPA and updated the tmux 2.1 shipping in Ubuntu 16.04 to a tmux 2.6. The arrow key problem disappeared.

How to set color of arrow head in Inkscape


This is a strange way that Inkscape is designed. Here is how I drew a red line with an arrowhead:

  1. Draw a straight line
  2. Set color of line to red
  3. Add arrow head or tail to the line

The problem is that the arrow head remains in the default black color! It is not set to red.


Inkscape designers are very well aware of this problem since a clean solution exists and is tucked away in the far recesses of its menus. To set the arrow head or tail to the same color as the line its attached to: go to Extensions -> Modify path -> Color markers to match stroke.

That is it, the color should be changed now. You will need to keep applying this command whenever you change color of the arrow line.

Tried with: Inkscape 0.48.4 and Ubuntu 14.04

How to disable arrow keys in Vim

Vim experts keep chanting that to really learn and love Vim, one must use the insert mode for the tiniest period of time and get out of it as soon as possible. However, this is a difficult skill to learn. This is because one can easily navigate in all directions in both insert and normal mode using the arrow keys.

So, one has to be forced to navigate using only hjkl keys. These keys cannot be used in insert mode, so one is forced to quit insert mode as soon as possible and learn other tricks to repeat edits.

Steve Losh recommends disabling the arrow keys for learning this skill. I was initially skeptical, but it worked extremely well for me within just 2 days!

To disable the arrow keys, add this to your vimrc:

Tried with: Vim 7.3 and Ubuntu 12.04 LTS